Code coverage services are only free for open-source projects (e.g. hosted on GitHub), so we should only handle them on Travis.
Also, it seems that codecov is a good alternative to coveralls, which has been partially failing for a while (no detailed coverage because "SOURCE NOT AVAILABLE", see here for example, even though the source code is openly available on GitHub...).
Code coverage services are only free for open-source projects (e.g. hosted on GitHub), so we should only handle them on Travis.
Also, it seems that codecov is a good alternative to coveralls, which has been partially failing for a while (no detailed coverage because "SOURCE NOT AVAILABLE", see here for example, even though the source code is openly available on GitHub...).